Evaluation of Hydrothermal Treatment to Immobilize Hexavalent Chromium in Wastewater Using Granulated Blast Furnace Slag

Synthesis of Hydrogarnet from Blast Furnace Slag Using Alkali Fusion for HCl Gas Removal

“…Regardless of particle size and heating temperature, mixtures of katoite [Ca 3 Al 2 (SiO 4 ) 2 (OH) 8 ], which is one of the hydrogarnet minerals, calcite (CaCO 3 ) and hydrocalumite [Ca 4 Al 2 O 6 (OH) 2 ･11H 2 O] can be synthesized from BF slag. There are many studies for the synthesis of functional materials from BF slag under hydrothermal condition, and in these studies, very fi ne BF slag (less than 300 μ m) is used as raw material, mixed with the sources of silica, alumina and calcia, such as quartz, α -alumina, lime and so on, to synthesize the product at more than 100°C for securing the synthesis reaction [4,[26][27][28][29][30][31][32]. Hydorgarnet syntheses from coal fly ash and molten slag are also similar experiments [17,18].…”

Effect of Temperature on Hexavalent Chromium Formation in (Al,Cr)₂O₃ with Calcium Aluminate Cement in Air

“…The pH of the leach solution increased from pH 7.3 of the distilled water to range from 10.91 to 9.54. During the leaching process, Ca and Al containing cement phase presumably dissolved in water as Ca 2 + and Al(OH) 4 − , which increased the pH of the leach solution. 38) And the amount of chromium ions in the leach solutions was also quantified with ICP.…”

“…Cr 2 O 3 has excellent corrosion resistance and thermal shock resistance, its use can reduce the materials consumption of any refractory system, 1,2) and it was often used as linings of the glass tank, gasification, waste melting furnaces and pyrometallurgical processes. [3][4][5][6] But the Cr 2 O 3 (III)-containing refractories can be oxidized to Cr(VI) in the presence of alkali metal and alkaline earth metal-oxides like K 2 O, Na 2 O and CaO. [7][8][9][10][11][12][13] Cr(VI) is known to be highly soluble in water and toxic and thus easily enter into ground water and food chain, [14][15][16][17][18] which poses a serious threat to the human and environment.…”

Estimation of the Environmental Impact for Recycling Blast Furnace Slag with a Hydrothermal Reaction Based on Life Cycle Inventory Data

“…The reactions and products can be used for the synthesis and production of functional ceramics from pure substances or wastes. [6][7][8] They can also be used in the immobilization process for forming a hydrothermal phase and incorporating heavy metals into that phase. 9,10) As a result of further study, if a number of such products that incorporate iron and steelmaking slag can be commercialized, such as ALC, this would represent a significant contribution to the field of steel slag recycling.…”